Dorchester, Mass. — The two men sit in a car on the edge of the Burger King parking lot. Soon they will go inside, where one will eat fries – he calls them his biggest vice – while the other, who wants to lose weight, drinks a diet Coke. Now they point out the apartment building in front of them: yellow brick, with cherry trees in bloom.

"That's where my son was murdered," says one of the men. His face barely registers emotion as he speaks, not because there's no pain but because this is a story Michael Person has told innumerable times. His son, Michael Greene, had done good and bad in his short life. At 26, having just signed a record deal, Greene seemed poised to turn a corner before he was shot to death during a 2001 dispute over drug turf.

The story is wrenching in itself but cuts deeper when Mr. Person explains that he also lost his sister, brother, nephew, and niece to homicide. And this particular spot, an unremarkable corner of Columbia Road and Washington Street, has a terrible history of its own: two murders since Greene's as well as the homicide of Person's nephew a block away.

At first glance Person and Mr. Dickerson – who together lead the First Response Ministry of the Greater Love Tabernacle Church (GLT), which seeks to both curb violence and support those victimized by it – seem not to have much in common. Although both grew up here in large African-American families, their lives followed different trajectories.

Person took a more circuitous path to the point of intersection the two men now share. A self-described former player in the street scene, Person dropped out of high school, and, after becoming a father at 18, turned to hustling before joining the Army in 1978 and slowly, over a period of decades, righting his life.

Despite the differences, Person and Dickerson are now close friends bound by the urgency of their mission. Together they offer GLT's complex mix of comfort to homicide victims' families, tough love to those who witnessed or participated in a crime, and preventive education for those not yet caught in the street.

Others involved in the fight against urban violence hold First Response in high regard. "To know that there are supports in place by fellow community members is hugely important," says Janet Connolly, deputy chief of staff for the Boston Police Department. "It's exactly what the city needs."

The help received from Person and Dickerson is "invaluable," according to Suffolk County District Attorney Daniel Conley. "An important part of [their] credibility is that they've never compromised their independence even as they've worked toward the same goals that we in law enforcement have."

When a homicide occurs, Person may go to the scene and escort the family to the hospital while Dickerson remains in the neighborhood trying to defuse tensions. During the ensuing days, they continue to support the community and help plan a funeral for the victim. They also work to get witnesses to come forward and perpetrators to turn themselves in, typically accompanying them to the police station.

The two men have a close and mutually respectful relationship. "He has a heart for the people," Person says of Dickerson. "He can find goodness in the worst person in the world." Person pauses, blinks. "He is more than a brother."

• • •

By the 1990s, Person had turned his own life around after years of street life. While working as a cook at various city programs for youth offenders, he discovered an interest in outreach. He also remarried, became a born-again Christian, and got involved in the ministry.

At their home, Person and his wife instituted "family night." Every Wednesday, the couple and their four children – three grown – gathered to share a meal chosen by the kids and cooked by Person. The rule during dinner was that the kids got to talk, while the parents just listened.

It was on one of those Wednesdays that Greene, who attended regularly, failed to show up. A full day passed before anyone could bear to tell Person what had happened, and 13 more before his son's body was returned to him.

After the death, Person turned to his youth work with greater urgency. He was appointed the city's TenPoint Coalition liaison to the victim/witness program at the D.A.'s office. After he was ordained a reverend in 2001 at Christ Temple Church, he founded the First Response Ministry. Last October he became a member of GLT and transferred the program there.

As director, his role, while unpaid, is more hands-on than Dickerson's. Inside his many files is a master sheet simply titled "Homicides." On it he lists each victim's name, the location and date of the crime, and the cause of death. Pink highlighter indicates the active cases – currently more than 20.

If there's an edge of desperation to the First Response mission, it is because the city's murder rate has not shown a substantive decrease in more than a decade. As a result, although Dickerson and Person are both trained grief counselors and know much about consoling families, they also aim a pointed message of accountability and restraint at those who may have witnessed (or participated in) the crime.

Funerals are often the place where that message is delivered. Dickerson gave the eulogy at a 2006 memorial service for 20-year-old Analicia Perry, shot while kneeling to light a candle at the makeshift shrine of her brother, who had been killed at the same location.

"If you know who did this, give him up," Dickerson shouted that day from the pulpit. He told the mourners to go ahead and cry, but less for Perry than for themselves. She was in heaven, he said, while everyone else was still "here in this cold-blooded world."

Although both men are Evangelicals who freely cite the Bible, their work crosses boundaries of faith and culture. Often they sit in court with witnesses who speak little English, advocating for them amidst intimidating circumstances. They have attended memorial services inside a mosque and a Buddhist temple, and no matter who calls, no matter when, they rush to the scene – sometimes arriving before the crime scene has been secured.

Both men see the African-American church as playing a key role in stemming urban violence, through direct action and partnerships with schools and police agencies. Dickerson is particularly quick to acknowledge the value of religion of any kind in the lives of youths. "It's been shown that young people who have faith are less likely to be involved in criminality," he says.

• • •

With his natural grace and oratory skills, Dickerson likely would have succeeded in the ministry almost anywhere. Instead, he chose to return to where he was raised. Dorchester is a proud place, one that over the decades has absorbed successive waves of immigrants and struggled to rid itself of poverty and violence.

Dickerson won't reveal exactly where he lives, out of concern for his family's privacy, but he and his wife have raised three children here. He is a thoughtful man who does not smoke, drink alcohol (or coffee), or eat red meat. That's not to say he stands apart from the world: He texts from his cellphone and dresses elegantly. When he laughs, his eyes light up.

Yet the work is taxing. Person has had serious health challenges, while Dickerson's face in repose holds a certain weariness. "He feels all of it," Person says of Dickerson. "I know him. I can see the pain."

Both men are mindful that their cellphones may ring at any moment. Recently Dickerson eulogized a young murder victim. After the service a boy approached. The service was impressive, he told Dickerson: "I want you to do my funeral." Person's eyes take on a haunted look as he recounts the story. "That's what this kid was thinking about. His funeral," he says. "That's what he saw in his future."